Question 1)a) What do you mean by electro-deposition? Describe clearly the various factors on which quality of the electro-deposition depends.
b) An electric train starts from rest with a uniform acceleration of 2Kmph/sec for 30 seconds and is moving up a gradient of 1%. The tractive resistance is 40N/tonne. Effect of rotational inertia is 10%. The coasting period is 50 seconds and the braking period is 20 seconds. The station stop is 15 seconds. The combined efficiency of gear and motor is 75%. Calculate the schedule aped and specific energy consumption.
c) Explain the requirements of good heating elements used in electric heating systems?
Question 2)a) List out the various requirements of an ideal traction system.
b) A small piece of wood measuring 8cm×3cm×1cm is placed between two electrodes each measuring 32cm×3cm. The distance between them is 2cm. A voltage at 20MHz is applied to the electrodes for heating the plywood. If the power consumed by the heating process is 2KW, find (i) the voltage applied across the electrodes and (ii) the current through the plywood piece. The plywood has a permittivity of 5 and a power factor of 0.005.
c) Two DC traction motors each having a resistance of 0.3ohm and when connected in parallel across 500V draw a current of 50A each and run at 700rpm and 750rpm respectively. Now, if they are connected in series, each taking a current of 50A on 500V mains, find the speed and voltage across each machine.
Question 3)a) Define the term ‘Welding’. Explain with a neat sketch the process of Flash butt welding.
b) Explain with a neat sketch the construction and working of a Coreless type high frequency induction furnace.
c) A train weighing 500 tonnes is going down a gradient of 20 in 1,000. It is desired to maintain a speed of 40Kmph by regenerative braking. Calculate the power fed to the line. The tractive resistance is 40N/tonne, the effect of rotational inertia 10% and efficiency of conversion is 75%.